1-Bromopropane → 1-Propyl-1H-imidazole-4-carbaldehyde

Participants

Reaction Steps

Imidazole-4-carboxaldehyde (30 g, 0.31 mol) was added portionwise to a solution of sodium hydride (13.9 g, 60% dispersion in mineral oil, 0.348 mol) in tetrahydrofuran (450 ml), and the solution stirred for 45 minutes. n-Propyl bromide (31.2 ml, 0.344 mol) was then added portionwise, followed by 18-crown-6 (150 mg), and the reaction heated under reflux for 18 hours. Aqueous ammonium chloride solution was added to the cooled reaction, and the mixture extracted with ethyl acetate (2×) and dichloromethane (2×). The combined organic extracts were dried (MgSO4), filtered, and concentrated under reduced pressure. The crude product was purified by column chromatography on silica gel, eluting with ethyl acetate:pentane (40:60), to give the title compound, 20.2 g, 47% yield.

Provenance & Evidence